微波助离子液体中硫-钕共掺杂TiO2催化剂的制备及其微波强化光催化活性

在离子液体介质中，采用溶胶-凝胶法，以钛酸四丁酯为前驱物，用微波干燥法合成S和Nd共掺杂纳米TiO₂光催化剂TiO₂-S-Nd。分别采用IR、XRD、BET和SEM对催化剂结构进行测试与表征，以甲基橙为模拟污染物，在微波超声波组合催化合成仪中，恒温（25 ℃）下分别利用微波辐射、紫外光照及微波辐射+紫外光照3种降解条件，着重考察Nd掺杂量和S掺杂量对TiO₂-S-Nd光催化活性的影响。结果表明，在离子液体用量5.6 mL、n(Nd)∶n(Ti)=0.015和n(S)∶n(Ti)=2时，经功率为350 W的微波加热干燥处理20 min的半成品催化剂，再在700 ℃高温炉焙烧2 h,制得TiO₂-S-Nd催化剂，具有较高的光催化降解活性。且在3种降解条件下，TiO₂-S-Nd对甲基橙降解率分别为12.11%、88.91%和100%，表明微波与紫外光照有较好的协同作用，即微波-紫外光照具有强化S和Nd共掺杂TiO₂-S-Nd催化剂降解甲基橙的效果，并且所制得的共掺杂TiO₂-S-Nd催化剂的光催化活性均高于单一S 或Nd掺杂TiO₂的光催化活性，说明S和Nd共掺杂也具有协同作用。

Microwave assisted preparation of S and Nd codope nano-TiO2 photocatalysts in ionic liquids and microwave strengthening photocatalytic activity

Using Ti(OBu)₄ as the precursor,S-Nd co-doped nano TiO₂ photocatalysts TiO_2-S-Nd were prepared by sol gel method in ionic liquids and microwave drying method.The structure of the catalysts were characterized by IR,XRD,BET and SEM.At the constant temperature (25 ℃),under the illumination and radiation conditions of MW,UV,MW/UV,the effects of doping amounts of Nd and S on photocatalytic activity of nano particle TiO₂-S-Nd for degradation of methyl orange were investigated in the combination of catalytic synthesis instrument with microwave ultrasonic.The results indicated that TiO₂-S-Nd catalyst possessed the highest catalytic activity,which was prepared under the following condition:ionic liquid dosage 5.6 mL,n(Nd)∶n(Ti)=0.015,n(S)∶n(Ti)=2,and the semi finished catalyst dried with the microwave heating at power 350 W for 20 min,then calcined at 700 ℃ in a high temperature furnace for 2 h.The degradation rate of methyl orange over TiO₂-S-Nd catalyst were 12.11%,88.91%,and 100%,respectively under the dagradation conditions of MW,UV and MW/UV,which showed that MW had good synergy with UV,and MW/UV had the strengthening effect for degradation of methyl orange over TiO₂-S-Nd catalyst.The photocatalytic activity of TiO₂-S-Nd catalyst were higher than that of S or Nd doped TiO₂ catalyst,which indicated that S and Nd codope had a synergistic effect.